Traffic chaos on Canberra Ave near HMAS Harman due to a multi-car crash this morning. Photo: Colleen Petch

No serious injuries were reported, but ACT Policing said the traffic jam quickly built up to be as far back as HMAS Harman near the NSW border at one stage.

It took at least 45 minutes for tow trucks to arrive to clear the crash scene. Police said at 10am the lane had been reopened, but officers were still on scene. Motorists were asked to slow down in the area.